So can Mylar filters. Glass filters are not superior to properly made Mylar filters. On Jan 14, 2012 12:04 PM, <erikhansen@thebluezone.net> wrote:
"Be careful when using this material!"
I agree, solar films should be inspected for pin holes regularly. Glass filters can be touched up with paint or a magic marker.
It's a good news/bad news situation.
The good news is that all the SunSpotters are complete!
The bad news is that the Baader filter material I used is FULL of pinholes and I must replace it in all of them.
I used a piece I bought from Astro-Physics some ten years ago. After performing the system checks and seeing all the pinholes, I checked the sheet that I cut them from, and, sure enough, it is loaded with defects.
Be careful when using this material!
I have a new sheet that I purchased just last year and will cut the replacements from it tomorrow. I haven't checked it yet but I'm hopeful that it's defect-free. It's still rolled in the shipping box that it arrived in.
The only other alternative is to black-out the pinholes with a sharpie. They are not actually "holes" through the mylar, but tiny specks where the aluminum coating has either detached from the substrate, or it could be that the substrate was dusty at the time of deposition. Manufacturing flaws.
Tiny "thin spots" where some filtering is taking place are not a problem, especially on a small aperture scope like these, but areas with no filtration at all are not acceptable.
Stay tuned, and my apologies on behalf of Baader. If all goes well I'll be distributing the scopes next week.
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